Trane CVHH, Инструкция по установке, эксплуатации и обслуживанию

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Start-up and Shut-dow n
CVHH-SVX001A-EN 83
tw o w eeks. This w ill prevent the accum ulation of
air and noncondensables in the m achine. To start
the purge, change the purge m ode to ON in the unit
control “ Settings Purge” m enu. Rem em ber to turn
the purge m ode to “Adaptive” after the tw o-hour
run tim e.
EarthWise Purge Sequence of
Operations
A Tracer UC800 controller that is configured to control a
purge system uses the operational sequences described in
this section.
Purge Operating M odes
Purge operating m ode options are as follow s:
Stop.
The purge condensing unit does not run in this
m ode.
On.
The purge condensing unit runs continuously in this
m ode, regardless of the chillers operational status.
Auto.
The purge condensing unit runs in this m ode, if the
m ain com pressor of the chiller is operating.
Adaptive.
The purge condensing unit operation depends
on past purge activity.
Adaptive M ode
The objectives of operating the unit in the adaptive m ode
are to:
• Enable purge system operation
• Enable the refrigeration circuit to effectively
accum ulate non-condensables w hether or not the
chiller is running
• Provide inform ation to an operator regarding w hether
leakage is on the high-pressure or low-pressure side of
the chiller
• Decrease energy usage by running the purge
refrigeration circuit only w hen needed to rem ove non-
condensables, rather than running it continuously
The adaptive m ode requires historical operating data so
that the controller can m ake optim al decisions regarding
how to run the purge refrigeration circuit in the future. On
initial start-up of a chiller that is in adaptive m ode, the
purge refrigeration circuit runs continuously for 168 hours
(7 days). The chiller com pressor m ay or m ay not be
running during this period.
Follow ing the initial data collection period, the adaptive
m ode custom izes the purge refrigeration circuit operation
during tw o distinct chiller operating conditions:
• Chiller com pressor On
• Chiller com pressor Off
Adaptive M ode Process—Chiller Compressor
On
Figure 48, p. 84 , illustrates the process described in this
subsection.
When the chiller com pressor starts, the purge refrigeration
circuit starts. The purge refrigeration circuit continues to
run until 60 consecutive m inutes of running occur w ithout
any pum p-out of non-condensables. The Pum pout Tim e is
the greater of the follow ing tw o values that the controller
has been tracking:
• The pum p-out tim e w ith the chiller On, over the last
24 hours
• The average daily pum p-out tim e w ith the chiller On,
over the last 7 days